ABSTRACT
PURPOSE: To describe the characteristics of adverse event reporting in the United States (US) Food and Drug Administration Adverse Event Reporting System (FAERS) before and after the outbreak of the COVID-19 pandemic. METHODS: We included all FAERS reports from the US and Canada from November 7, 2019 to July 15, 2020 and divided the study period into three equal time intervals (pre-pandemic, first pandemic, second pandemic). We focused on methotrexate, a broadly used drug unrelated to COVID-19, and (hydroxy)chloroquine, another broadly used drug implicated in COVID-19 treatment. Using descriptive statistics, we compared reporting characteristics before and after the COVID-19 outbreak. RESULTS: During the study period, 366 998 cases (60% female, median age: 59 years) were submitted to FAERS. The daily median number of reports (1796 in the pre-pandemic, 1810 in the second pandemic time interval) and other characteristics remained stable. The daily median number of reports for methotrexate decreased from 28 in the pre-pandemic to 15 in the second pandemic time interval, with no considerable differences in other characteristics. The daily median number of reports for (hydroxy)chloroquine increased slightly from 1 in the pre-pandemic to 3 in the second pandemic time interval, while there were also changes in the demographics of cases and an increase in the proportion of cases reported by health professionals. CONCLUSIONS: The overall reporting to FAERS did not change after the outbreak of the COVID-19 pandemic. However, some stimulated reporting was observed for (hydroxy)chloroquine, highlighting the need for caution when conducting pharmacovigilance analyses with substances related to COVID-19.